Question

Megan and Sam together take 12 minutes to wash a car. Washing the car by herself Megan took 21 minutes. How long would it take Sam to wash the car?

Answer 1

let x = sam's time
y = megan's ime

use the formula
\[\frac tx + \frac ty = 1\]
where t is total time

now substitute
\[\frac{12}{x} + \frac{12}{21} = 1\]
now we solve for x.

Answer 2

do you need more help?

Answer 3

Can you solve for x and show me the steps?

Answer 4

subtract both sides by \(\frac{12}{21}\)

\[\frac{12}{x} = 1 - \frac{12}{21}\]
\[\frac{12}{x} = \frac{21}{21} - \frac{12}{21}\]
\[\frac{12}{x} = \frac{9}{21}\]
multiply both sides by x
\[12 = \frac{9}{21} x\]
multiply both sides by 21
\[12 \times 21 = 9x\]
divide both sides by 9
\[\frac{12 \times 21}{9} = x\]
simplify

Answer 5

i need to go now so i hope you got that!